Wave data were obtained with a capacitance-type, partially submerged, wire probe. Pitch 

 data were obtained with a gyroscope located amidships. Heave data were obtained with a 

 linear displacement potentiometer installed on the moving arms of a special pantograph at the 

 LCG. Pitch and heave data were also computed from direct measurements of the sum and the 

 difference of the instananeous accelerations recorded by two vertical accelerometers located 

 at equal distances fore and aft of the LCG. Motion data were also obtained with a 35mm movie 

 camera. 



The principal fin configuration, Fin No. 1, was equipped with two bending flexures on 

 each side, to obtain data on strain due to bending moments experienced by the fin in waves. 

 Each flexure had a complete four-active-arm bending bridge. The flexures were calibrated 

 prior to testing. 



In addition to the instrumentation described above, the model was equipped with an 

 electric motor driving the propeller, a propeller shaft tachometer, an independent vertical 

 accelerometer located at the bow, and an angular displacement type potentiometer for surge 

 data. 



Figure 7 shows the layout of the instruments. 



TEST PROGRAM 



The tests were conducted at a model displacement of 2699 pounds, corresponding to 

 17,505 tons for the ship. The draft was 12.4 inches even keel, corresponding to 25 feet full 

 scale. The tests originally called for a displacement corresponding to 15,870 tons at a mean 

 draft of 23 feet, with a trim of 4 feet by the stern. Tests at this load condition, however were 

 discontinued because the model without the fins exhibited frequent forebody emergence, occa- 

 sionally extending to more than one-half the ship's length. The design displacement of the 

 Mariner is 21,093 tons at a draft of 29 feet 10 1/16 inches even keel. 



Tables 2 and 3 give the speed and wave size schedules, respectively, of the tests. 



TABLE 2 



Schedule of Tests - Speed 



Speed, knots 



i 



F 

 n 



Model 



Ship 





 1 

 2 

 3 

 4 







4.82 



9.64 



14.46 



19.28 





 0.065 

 0.129 

 0.191 

 0.255 



10 



